Background: Metabolic, inflammatory, and autonomic nervous system dysfunctions are present in patients with heart failure (HF). However, whether these changes are due to left ventricular dysfunction or heart failure is unknown.
Methods: We evaluated metabolism and inflammatory activity in patients with idiopathic dilated cardiomyopathy (IDC) and chagasic cardiomyopathy (CHG) and their correlation with the autonomic nervous system (ANS). Forty-six patients were divided into 3 groups: IDC, CHG, and control (CG). All patients underwent anthropometric measurements. Levels of adiponectin, leptin, insulin, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) were assayed in serum samples using ELISA. ANS was assessed by heart rate variability in time and frequency domains on a 24-hour Holter monitor. High-frequency (HFr) component values were used to estimate parasympathetic activity, and low-frequency (LFr) component values were used for sympathetic activity. Analyzes were made of the correlations of each of the metabolic parameters (insulin, leptin, and adiponectin) with the inflammatory cytokines (interleukin-6 and TNF-alpha) and with ANS assessment measurements.
Results: No differences were noted between groups regarding blood glucose levels, total cholesterol, leptin, and adiponectin. Insulin levels were lower in CHG 5.4±3.3 μU/mL compared with that in CG 8.0±4.9 μU/mL and IDC 9.9±5.0 μU/mL (p=0.007). Levels of interleukin-6 and tumor necrosis factor-alpha were also higher in CHG compared with that in the other groups. Insulin was positively associated with leptin (r=0.579; p=0.024), LFr/HFr ratio (r=0.562; p=0.029), and with the LFr component (r=0.562; p=0.029) in CHG. Insulin levels were negatively associated with adiponectin (r = -0.603; p=0.017). The addition of an adiponectin unit reduced average insulin by 0.332 ug/mL. A decrease was noted in insulin levels in CHG compared with that in IDC and CG. Insulin levels were associated with ANS parameters and adiponectin.